"From the moment I walked in the door here, this is where I wanted to be for the rest of my life. I've been here for three and a half years already and to sign another four-year deal is great. I can't wait for the future.

"Celtic is a great club and I wouldn't want to be anywhere else. I had the opportunity to move but I wanted to stay and fight for my place. I've been rewarded with another deal and knowing that I'm going to be here for another four years is great."

Griffiths has made four appearances in Scotland's top flight this season.

He scored his 100th goal for Celtic in the Europa League play-off second-leg win over Suduva at the end of last month.